You have not mentioned what kind of nanoparticle you synthesized. Even so, as far as I know, there is no universal solvent for nanoparticles of any type. I think what you need do is to functionalize it with chemical substances that make it soluble in the solvent of your interest. Another way is search for a chemical route that results at soluble nanoparticles in colloidal form.
Dear sir, Thank you for your valuable suggestion. Literature survey reveals that to do the antibacterial activities of nano particles, nano particles should be added in the form of solution into the agar media containing bacterial strains. For this suitable solvent to dissolve the nano particles is needed.
So you need to disperse your particle in a suitable solvent not dissolving them. You used a wrong expression. Anyway this is easy in most cases and it will depend on the preparation method. Mainly the solvent and the capping agent. If the surface of your particles is hydrophilic you can disperse them in alcohol or water depending on the nature of the particles. If they are hydrophobic you can disperse them in hexanes. However I do recommend that you functionalize your particles surface and make hydrophilic for the bio-test. Good luck.
You need to make the distinction between dissolution and dispersing. Dissolving a substance will refer to mixing of the solute and dispersion medium at molecular or atomic level. However, nanosized materials can be dispersed in appropriate continuous medium (dispersion) without the size and shape being comprised. See answer by Ahmed A. Farghaly.
In most of the cases metal oxides does not dissolve and it only disperse in a solvent whatever you used for dispersion. If suppose your metal oxides may have hydrophilic groups on their surface it may dissolve in polar solvents such as water, ethanol etc. If this is the case you can try to dissolve in any of the polar solvents.
In case of copper nano particles. Literature survey reveals that synthesized copper Nanoparticles must be dissolved in DMSO (dimethyl suffuse oxide) or DMF (dimethyl formalise) for antibacterial activity.
Do you have any idea regarding the dispersion of Nickel oxide nannoparticles with any solvent? Originally, the nanoparticles has to be dissolved (you people use dispersed) in the solvent, so that it can express its antimicrobial activity when we load in to the agar plates. If the particles dispersed, obviously it could not express a good antimicrobial activity. Also, nickel oxide particles cannnot be synthesized in liquid portion, as it needs a high temp. heating to occur synthesis.
I have used ethanol and DMSO, but everything works partially and not a complete solvent,
So, considering the antimicrobial activity, any of you can suggest a good solvent to dissolve/disperse Nickel oxide nanoparticle?